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birch

(Encyclopedia)CE5 White birch, Betula papyrifera birch, common name for some members of the Betulaceae, a family of deciduous trees or shrubs bearing male and female flowers on separate plants, widely distribut...

dust, atmospheric

(Encyclopedia)dust, atmospheric, minute particles slowly settling or suspended by slight currents and existing in varying amounts in all air. There is least dust at high levels over the ocean and most at low levels...

mulch

(Encyclopedia)mulch, any material, usually organic, that is spread on the ground to protect the soil and the roots of plants from the effects of soil crusting, erosion, or freezing; it is also used to retard the gr...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...

hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

cautery

(Encyclopedia)cautery, searing or destruction of living animal tissue by use of heat or caustic chemicals. In the past, cauterization of open wounds, even those following amputation of a limb, was performed with ho...

assaying

(Encyclopedia)assaying əsāˈyĭng, ăsˈāyĭng [key], in metallurgy, process of determining the specific metallic content of an ore, alloy, or other substance, especially one containing precious metals. It consi...

hashish

(Encyclopedia)hashish hăshˈēsh, –ĭsh [key], resin extracted from the flower clusters and top leaves of the hemp plant, Cannabis sativa, and C. indica. Hashish, called charas in India, is the most potent grade...

explosive

(Encyclopedia)explosive, substance that undergoes decomposition or combustion with great rapidity, evolving much heat and producing a large volume of gas. The reaction products fill a much greater volume than that ...

Ratnapura

(Encyclopedia)Ratnapura rŭtˈnəpo͝orə [key] [Sinhalese,=city of gems], town (1995 est. pop. 46,000), SW Sri Lanka. Located in a rubber- and rice-producing area, Ratnapura is Sri Lanka's major precious-stone cen...